package com.sunxueqi.common.util;

import org.springframework.aop.framework.AopContext;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.stereotype.Component;

/**
 * spring工具类，方便在非spring管理环境中获取bean
 * @author Sun
 *
 */
@Component
public class SpringUtils implements BeanFactoryPostProcessor{

	/**
	 * spring应用上下文环境
	 */
	private static ConfigurableListableBeanFactory beanFactory;
	
	@Override
	public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
		SpringUtils.beanFactory = beanFactory;
	}

	@SuppressWarnings("unchecked")
	public static <T> T getBean(String name) throws BeansException{
		return (T)beanFactory.getBean(name);
	}
	
	public static <T> T getBean(Class<T> clazz) throws BeansException{
		T result = beanFactory.getBean(clazz);
		return result;
	}
	
	/**
	 * 如果BeanFactory包含一个与所给名称匹配的bean定义，则返回true
	 * @param name
	 * @return
	 */
	public static boolean containsBean(String name) {
		return beanFactory.containsBean(name);
	}
	
	/**
	 * 判断以给定名字注册的bean定义是一个singleton还是一个prototype。
	 *  如果与给定名字相应的bean定义没有被找到，将会抛出一个异常（NoSuchBeanDefinitionException）
	 * @param name
	 * @return
	 * @throws NoSuchBeanDefinitionException
	 */
	public static boolean isSingleton(String name) throws NoSuchBeanDefinitionException{
		return beanFactory.isSingleton(name);
	}
	
	/**
	 * Class 注册对象的类型
	 * @param name
	 * @return Class 注册对象的类型
	 * @throws NoSuchBeanDefinitionException
	 */
	public static Class<?> getType(String name) throws NoSuchBeanDefinitionException {
		return beanFactory.getType(name);
	}
	
	/**
	 * 如果给定的bean名字在bean定义中有别名，则返回这些别名
	 * @param name
	 * @return
	 * @throws NoSuchBeanDefinitionException
	 */
	public static String[] getAStrings(String name) throws NoSuchBeanDefinitionException {
		return beanFactory.getAliases(name);
	}
	
	/**
	 * 获取aop代理对象
	 * @param <T>
	 * @param invoker
	 * @return
	 */
	@SuppressWarnings("unchecked")
	public static <T> T getAopProxy(T invoker) {
		return (T) AopContext.currentProxy();
	}
		
}
